<html>
    <head>
        <script src="../zhe_repo/vue.js"></script>
    </head>
    <body>
        <div id="app3">
            <h1 v-if="seen">您看得见！</h1>
        </div>
        <script>
            var app3 = new Vue({
                el: "#app3",
                data: {
                    seen: true
                }
            })
        </script>
    </body>
</html>